The use of cellulosic materials as insulation has been well known for many years. Cellulosic insulation is a very attractive product for many reasons. It is one of the best insulating materials available, having a very high R value. It uses as a raw material a product which is normally a waste material, used newsprint, and upgrades it to fill an important need in society. Cellulosic insulation is readily adaptable to refit applications in existing structures and for blowing into attics in both new and existing buildings. When correctly made and treated, cellulosic insulation is one of the safest types of insulating materials, and actually provides fire protection.
Cellulosic insulation is typically treated with boron compounds, specifically boric acid and borax combinations to impart fire retardancy. In order to meet current flammability specifications, and to offset the high prices and limited supply of boron compounds, other salts, especially salts involving nitrogen, phosphorous or aluminum, such as ammonium sulphate, aluminum sulphate, aluminum hydrate, ammonium phosphate, sodium tripolyphosphate and others are used as partial or total replacements for the boric acid, borax combinations. Although these salts provide satisfactory fire retardancy, they are generally corrosive to steel, copper, and aluminum. Since the cellulosic insulation is typically used in attics, walls, and other areas where it will come in contact with pipes, conduits, and other metal surfaces, the corrosive nature of these salts is a serious drawback to the use of cellulosic insulation.
The invention taught herein, overcomes the limitations of the prior art by treating the cellulosic insulation with an effective amount of special corrosion inhibiting materials.